Bis-phosphinimine catalyst

Abstract

Organometallic complexes having two phosphinimine ligands and at least one activatable ligand are catalyst components for olefin polymerization. Preferred polymerization systems are prepared by combining the organometallic complexes with an ionic activator and/or an alumoxane. Preferred catalyst components contain titanium, zirconium, or hafnium and are activated with an ionic activator to form catalysts for ethylene polymerization.

What is claimed is:  
     
       1. A catalyst component for olefin polymerization which is an unbridged bis-phosphinimine complex defined by the formula: 
       
         
           (Pl) 2 —M—L n    
         
       
       wherein M is a metal selected from group  2-14 10  metals; each Pl is independently a phosphinimine ligand defined by the formula:                    
       wherein each R 1  independently selected from the group consisting of (a) a hydrogen atom, (b) a halogen atom, (c) C 1-20  hydrocarbyl radicals which are (i) unsubstituted or (ii) further substituted by a halogen atom, (d) a C 1-8  alkoxy radical, (e) a C 6-10  aryl or aryloxy radical, (f) an amido radical, (g) a silyl radical of the formula:  
       
         
           —Si—(R 2 ) 3    
         
       
       wherein each R 2  independently selected from the group consisting of hydrogen, a C 1-8  alkyl or alkoxy radical, C 6-10  aryl and C 6-10  aryloxy radicals, and (h) a germanyl radical of the formula:  
       
         
           Ge—(R 2 ) 3    
         
       
       wherein R 2  is as defined above; L is an activatable ligand; n is 1, 2 or 3 depending upon the valence of M with the proviso that L is not a cyclopentadienyl, indenyl or fluorenyl ligand; and  
       B an activator.  
     
     
       2. The catalyst component according to  claim 1  wherein M is selected from group 4 and group 5 metals. 
     
     
       3. The catalyst component according to  claim 2  wherein each L is independently selected from the group consisting of a hydrogen atom, a halogen atom, a C 1-10  hydrocarbyl radical, a C 1-10  alkoxy radical, a C 5-10  aryl oxide radical; each of which said hydrocarbyl, alkoxy, and aryl oxide radicals may be unsubstituted by or further substituted by a halogen atom, a C 1-8  alkyl radical, a C 1-8  alkoxy radical, a C 6-10  aryl or aryl oxy radical, an amido radical which is unsubstituted or substituted by up to two C 1-8  alkyl radicals; a phosphido radical which is unsubstituted or substituted by up to two C 1-8  alkyl radicals. 
     
     
       4. The catalyst component according to  claim 1  wherein M is titanium (III) and n is 1. 
     
     
       5. The catalyst component according to  claim 1  wherein each R 1  is independently a hydrocarbyl group containing from one to twenty carbon atoms. 
     
     
       6. The catalyst component according to  claim 1  wherein each R 1  is tertiary-butyl. 
     
     
       7. An olefin polymerization catalyst system comprising a catalyst component according to  claim 1  and an activator. 
     
     
       8. The catalyst system according to  claim 7  wherein said activator is an alumoxane. 
     
     
       9. The catalyst system according to  claim 8  wherein each R 1  is tertiary butyl, n is 2 and each of said L is a halide. 
     
     
       10. The catalyst system according to  claim 7  wherein said activator is an ionic activator. 
     
     
       11. The catalyst system according to  claim 10  wherein each R 1  is tertiary butyl, said M is titanium, n is 2 and each of said L is a hydrocarbyl group having from one to twenty carbon atoms. 
     
     
       12. The catalyst system according to  claim 10  wherein said ionic activator comprises an organometallic boron complex containing one boron atom and at least three perfluorinated phenyl ligands bonded to said boron atom. 
     
     
       13. The catalyst system according to  claim 11  wherein each of said L is methyl. 
     
     
       14. The catalyst system according to  claim 12  which further contains alumoxane.